Social media companies like Facebook and Twitter could face fines of up to £2m for failing to combat online harassment, abuse and bullying under a new bill proposed by British MPs.

The Malicious Communications (Social Media) bill, a private members bill spearheaded by Labour MP Anna Turley, would see the formation of a register of social media firms that operate in the UK, regulated by Ofcom.

If passed into law, culture secretary Karen Bradley would be able to determine whether or not firms on the list were failing to filter “threatening content”, and issue penalties of up to five per cent of the companys annual global income, or £2m, whichever is greater.

The bill also proposes that social media firms should “have in place reasonable means to prevent threatening content from being received”, filtering what users can see unless they opt out of the service. Users under the age of 18 would not be able to opt-out, with firms having to ensure that age verification tools were in place.

According to an NSPCC report on child safety in the UK, over 4,500 calls were made to Childline in 2016 where cyber bulling was mentioned, a 13 per cent increase year-on-year.

“For many years social media platforms have been failing to protect their users from harmful abuse,” said Anna Turley MP. “Every day thousands of people are victims of intimidating, offensive, indecent, obscene or menacing messages which can cause a great deal of distress and harm, particularly to children and young people.

“This bill doesnt get in the way of free speech, it simply creates an optional filter for online abuse; a bit like a spam filter on your emails. These social media platforms already have highly sophisticated tools and algorithms that would enable them to screen out abusive content. Its about time they used them to protect people.”

Both Twitter and Facebook have faced consistent criticism over their approach to abusive and indecent material. Twitters problem with abuse is well-documented, and despite renewed efforts by the firm to combat harassment carried out using its platform, its reputation is thought to have scuppered potential deals with Salesforce and Disney last year when the company was seeking to sell itself off to a larger firm.

Facebooks most recent controversies have focused on fake news distributed via its network, but it has also seen criticism over failing to moderate content in its Live video product. High profile cases involving abuse, torture and graphic violence shared via live-streaming, and resurfacing later despite bans, have raised questions about the firms ability to control the feature, which it has been aggressively marketing in the past 12 months.

The Malicious Communications (Social Media) bill was first seen by parliament last year, and is due for a second reading the House of Commons next month, where it has received cross-party support. There has been growing awareness of online abuse and harassment among authorities in Britain, with Scotland Yard establishing a two-year, £1.7m project called the Online Hate Crime Hub last year that aimed to cut through the “veil of anonymity” used by abusers and cyber-bullies.